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Updated: Aug 11, 2026
A Simple Method for the Size Controlled Synthesis of Stable Oligomeric Clusters of Gold Nanoparticles under Ambient Conditions
Published on: February 5, 2016
A reversible polymorphic phase change which affects the luminescence and aurophilic interactions in the gold (I)
Emily M Gussenhoven1, James C Fettinger, David M Pham
1Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
Abstract:
Crystallographic examination of [mu3-S(AuCNC7H13)3](SbF6) shows that it undergoes a reversible phase change from orthorhombic to monoclinic upon cooling. At 190 K, the structure shows that two cations self-associate to form a pseudo-octahedral array of six gold atoms connected by both intra- and interionic aurophilic interactions. On cooling, the clusters become less symmetric, and in one, the interionic Au...Au separations increase, while they decrease in the second cluster. The luminescence of crystalline [mu3-S(AuCNC7H13)3](SbF6) shows corresponding changes in emission, with two emissions of similar lifetimes but with different excitations at 77 K, but only a single emission at 298 K. In contrast, [mu3-S(AuCNC6H11)3](PF6), which has a similar structure to that of the high-temperature form of [mu3-S(AuCNC7H13)3](SbF6), does not undergo a phase change or change in its luminescence upon cooling.
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